Ceramic oxides and mixtures thereof find utility as catalysts, ceramics, optical fibers, pigments, and superconductors. Mixed oxide powders such as SiO.sub.2 -Al.sub.2 O.sub.3, Al.sub.2 O.sub.3 -TiO.sub.2, TiO.sub.2 -V.sub.2 O.sub.5, SiO.sub.2 -TiO.sub.2, SiO.sub.2 -GeO.sub.2 and Y-Ba-Cu-O are used to produce catalysts, catalyst supports, ceramics, optical fibers, pigments, and superconductors. The degree of mixing of these ceramic oxides and their microstructures are critical to their reactivity, strength, refractivity, and electrical resistivity. Mixed ceramic oxides may be, for example, simple mixtures thereof, agglomerates, one ceramic oxide supported on another, or one ceramic oxide coated with another. The ceramic oxide may also be a compound formed from two different ceramic oxides, e.g., Al.sub.2 O.sub.3.TiO.sub.2. Mixed ceramic oxides are typically prepared, for example, by flame spraying mixed sols thereof or by coating a ceramic oxide by depositing it from a solution such as an aqueous silicate solution. These methods are characterized by difficulty in controlling the properties of the mixed ceramic oxide obtained.